The conditions of health and hygiene are improving in many countries; a growing life expectancy is a direct consequence of this.
Thus, the average age of the population in Europe is regularly increasing.
Projections for the 2060 timeframe reveal that the percentage of people over 65 should reach over 50% of the total population compared to scarcely 20% currently.
This general aging of the population motivates people involved in healthcare to find solutions to provide independence to the elderly as long as possible and to do so with a minimum assistance.
Among the various challenges raised by this general aging, one of the issues is to establish effective systems for detecting falls.
In fact, every year there are many falls involving a hospitalization because the fall was not detected in time; it should be noted now that the health of an elderly person can worsen very quickly when care after the fall is delayed too long.
In the state-of-the-art, there are several fall detection systems.
Among these systems are found:                those which must be carried at all times such as, for example, anti-fall patches, or else        those which are intrusive such as for example remote monitoring systems with image processing.        
There are other detection systems avoiding the above disadvantages.
To this end, the document WO 2006/130081 proposes a method for detection of a person getting out of bed. The method proposed in that document is particularly suited to old and/or handicapped people.
More specifically, pressure sensors, inserted in polyurethane foam are connected to a monitoring system which triggers an alarm when the pressure is exerted on the sensors.
Nonetheless, this method using pressure sensors is not suited to detecting falls. In fact, with such a method, it is impossible to distinguish a person who is walking from one who is falling.
Document WO 2009/050285 proposes a floor mat instrumented by a system composed of sensors. This system uses capacitance associated with the deformation of an intermediate layer for detecting without distinction the presence of a person or an object.
Just the same, the sensors inserted in this mat are not suited for detecting specifically the load transfers related to the presence of a person or an object.
Although interesting, the various solutions above do not allow a fine detection of someone's fall. Additionally, the installation of the solutions proposed above is very costly, difficult and tedious to implement.
Alternatively, with the incorporation of capacitive sensors into the floor of a room, the presence of people on the surface can be detected non-intrusively by measuring the variation of a physical magnitude.
In fact, a person on the floor is comparable to a local variation of the permittivity or to the presence of a new electrode.
In this context, capacitive sensors are the sensors of choice for detecting people. In fact, the capacitive sensors operate like capacitors and their capacitance varies when an object or individual comes close: this variation of the capacitance serves to determine whether an object or individual is present near the sensor.
The document FR 2,956,137 thus proposes a floor instrumented with such capacitive sensors for presence detection.
In that document, the floor comprises:                a sublayer made up of an electrically insulating material and placed on a slab;        capacitive sensors placed on the sublayer; and        a bed layer placed on the sublayer, where this bed layer is insulating and covers over the sensors.        
According to this document FR 2,956,137, it is indicated as essential for effective detection with capacitive sensors to have a sublayer made up of an electrically insulating material.
In this document, the installation of an instrumented floor with an electrically insulating sublayer is complex and costly.
The document WO 2014/053719 proposes a solution for avoiding such a sublayer. Thus, that document provides for a capacitive sensor comprising a specific disposition of a plurality of electrodes.
More specifically, in that document, the sensor comprises at least three electrodes extending longitudinally in one single direction.
According to a first advantageous characteristic from that document, to allow a finer detection of the fall of an individual or an object on the floor, the electrodes for the sensor are polarized independently of each other.
According to a second advantageous characteristic from that document, the geometry of the electrodes (radius of curvature of the electrodes and ratio of the separation distances) serve to improve the detection precision.
In any case, the advantageous features proposed in the document WO 2014/053719 do not make it possible to locate the precise position of the individual or the object once it is detected.
The Applicant submits that none of the prior art documents proposes a solution with which to detect and locate precisely the presence of an object or an individual on the floor.